1. Field of the Invention
The present invention relates to a printing unit and a thermal printer.
2. Description of the Related Art
Hitherto, a thermal printer has been known as a printer configured to perform printing on a recording sheet (heat-sensitive paper). The thermal printer includes a printing unit that can be reduced in size and weight, and has a simple configuration without using toner or ink. Therefore, the thermal printer is employed for cash registers or mobile terminal devices to be widely used to print various labels, receipts, and tickets.
As the printing unit described above, a so-called “separate-type” printing unit is known. In the separate-type printing unit, for example, a head frame configured to support a thermal head is mounted to a casing main body configured to receive, for example, a roll sheet therein, whereas a platen frame configured to support a platen roller is mounted to a printer cover that is coupled to the casing main body so that the printer cover can be operated to be opened and closed.
Further, a printing unit including a cutter unit configured to cut a printed recording sheet is known. The cutter unit includes a movable blade incorporated into, for example, the head frame of the above-mentioned frames, and a fixed blade incorporated into, for example, the platen frame of the above-mentioned frames. According to this configuration, the movable blade is slid relative to the fixed blade so as to nip the recording sheet between the movable blade and the fixed blade, to thereby cut the recording sheet.
Incidentally, in the printing unit, the thermal head may be replaced when a failure occurs in the thermal head due to wear between the thermal head and the platen roller or the like. As a method for replacing the thermal head, there is conceivable a method involving removing the movable blade from the head frame first, and removing the thermal head from the head frame thereafter. However, in the above-mentioned related-art configuration, the movable blade is fixed to the head frame with fastening members such as screws. Therefore, tools are necessary for the work of mounting and removing the movable blade, resulting in a problem of low maintainability. Further, in order to mount the movable blade, the above-mentioned fastening members are additionally necessary, resulting in a fear of the increase in number of components and manufacturing cost.
In view of the above-mentioned matters, a printing unit and a thermal printer capable of enhancing the maintainability while suppressing the increase in number of components and achieving cost reduction are demanded in this technical field.